Shopify's Legacy Script Tags Are Blocked: Why an App Just Stopped Working on Your Store

Something on your storefront has stopped working. The live chat bubble is gone, the exit pop-up no longer fires, the trust badges under the add to cart button have vanished, or your currency switcher has quietly started showing pounds to everyone. Nothing in the theme changed. The app is still installed and still billing you.

If this happened after 1 October 2026, and especially if it followed a reinstall, a theme update or a change to the app's settings, the likely cause is that Shopify's legacy script tags are now deprecated. The app was relying on an API that Shopify has started closing down, and the vendor has not finished moving off it. This article explains what changed, how to work out which of your apps are affected, and what to do while you wait (or decide not to wait).

What changed on 1 October 2026

Shopify announced the deprecation in its developer changelog on 24 August 2026. Since 1 October, the two API calls an app uses to add or edit a script tag (scriptTagCreate and scriptTagUpdate) fail on every API version, older ones included. The REST ScriptTag resource rejects the same operations. Developers are reporting it as a scriptTagCreate permission error; Shopify's own wording is a user error. Either way, the call does not go through and the app cannot put its script on your store.

Existing script tags were not deleted. If an app created its tag before the cutoff, that script still loads today. That is why the problem looks random: one store on the same app is fine, another that installed last week is not. Reinstalling to fix something else is a common trigger, because the uninstall removes the old tag and the reinstall cannot create a new one. Reading and deleting tags still works, so vendors can still audit and clean up.

The second date is the one that matters more. From 1 March 2027, Shopify stops injecting script tags into storefronts altogether. Anything still relying on one stops working on every store at once, whether the vendor has done anything or not. Shopify now also shows a dismissible banner in the admin when you install an app that still uses script tags. If you see it, do not dismiss it without reading it.

This is not the Shopify Scripts deprecation

The naming is unhelpful, so it is worth separating the two. Shopify Scripts were Plus-only Ruby scripts that controlled discount, shipping and payment logic at checkout. They stopped running on 30 June 2026 and the replacement is Shopify Functions. We covered that in Shopify Scripts Are Dead: What to Do If You Don't Have a Developer. If your automatic discounts broke, that is your article.

Script tags are a different thing. They are a way for a third-party app to inject its own JavaScript file into your storefront pages without touching your theme code. Most apps built before about 2021 used them because it was the easiest route. There was also a separate, earlier shutdown of script tags on the thank you and order status pages, which was part of the checkout extensibility changes. We wrote about auditing that in Shopify Checkout Extensibility Deadline Passed. What is left now is the storefront itself: home, collection, product, cart and account pages.

Which Shopify apps stopped working, or will

Shopify does not publish a list of affected apps, and there is no screen in the admin that shows you which apps hold a script tag. The categories that lean on them most are predictable:

Live chat and helpdesk widgetsPop-ups, exit intent and email capture overlaysTrust badges, payment icons and delivery countdownsCurrency converters and geolocation redirects (common on UK stores selling into the EU and US)Size charts, wishlists and back in stock buttonsOlder review widgets and older tracking or affiliate scripts that predate the Web Pixels API

Well maintained apps from larger vendors have mostly migrated already. The risk sits with older, cheaper or abandoned apps, particularly anything whose App Store listing shows no updates in the last year. Those are also, not coincidentally, the apps most likely to be dragging your page speed down. We looked at that in How Too Many Shopify Apps Are Slowing Down Your Store.

How to audit your store for script tags

Shopify's storefront deprecation guide gives app developers two replacement routes. Analytics and tracking code should move to a web pixel. Anything that renders something a shopper sees should move to an app embed block inside a theme app extension. Helpfully, both of those are visible to you as a merchant, which gives you a quick way to check what is modern and what is not.

Go to Online Store, Themes, Customize, then open App embeds in the left panel. Apps using theme app extensions show up here as toggles.Go to Settings, then Customer events. Apps using the Web Pixels API show up here as app pixels.List every installed app that puts something on the storefront. If it appears in neither place, assume it is using a script tag or old theme code injection until proven otherwise.Confirm in the browser. Open the Network tab in developer tools on a product page, filter by JS, and look for files loaded from the app vendor's domain rather than from your theme.Email each affected vendor with three questions: does your app use the ScriptTag API, have you shipped a theme app extension or web pixel yet, and what is your date for the March 2027 shutdown.

One trap to be aware of: app embed toggles are set per theme. If you have published a new theme, duplicated one for a seasonal campaign, or had a redesign go live, the embeds can be switched off on the new theme. A tracking app with its embed off looks identical to a broken tracking app. Check the toggles before you blame the vendor.

The fix path: wait, switch or rebuild

You will end up in one of three situations with each app, and the right move is different for each.

The vendor has already shipped the new version. Update the app, switch on the embed in the theme editor, and check the feature works. Then ask the vendor to remove the old script tag from your store. Running both at once means duplicate scripts, and for analytics apps that means double counted events in your reports.

The vendor says it is working on it. Get a date in writing. March 2027 is a hard stop, not a guideline. If there is no date by early December, start evaluating an alternative so you are not scrambling in February alongside every other merchant on the same app.

The vendor is silent or the app is abandoned. Switch. For simple features like trust badges, a size chart or a delivery countdown, a small theme section built by someone who knows Liquid is usually cheaper than another app subscription, loads faster, and does not have a third party's roadmap attached to it. Our Shopify theme design and development team does a lot of this kind of replacement work. For chat, reviews or subscriptions, pick an app that already lists theme app extensions or web pixels in its documentation, because that tells you the vendor is paying attention.

An app that disappears quietly costs more than one that breaks loudly. Nobody notices the pop-up is gone until the email list stops growing.

Treat the Shopify web pixels migration as a clean-up

It is tempting to see this purely as a nuisance Shopify has dropped on you. It is also an excuse to do the storefront clean-up most brands keep postponing. Every script tag is another third-party JavaScript file loading on every page view, and the apps most likely to rely on them are the ones you installed years ago and have not reviewed since. Most Shopify brands we meet do not have a traffic problem, they have a conversion problem, and a cluttered, slow storefront running widgets nobody has questioned is part of that.

So as you audit, ask a second question of each app alongside the technical one: does this still earn its place? If a countdown timer or a badge has never been tested against the page without it, this is the moment to find out. That kind of structured testing is what our Conversion Growth Retainer is built around, and the script tag deadline is a sensible place to start it.

What to do this week

Walk through App embeds and Customer events, write down every storefront app that appears in neither, and send those vendors the three questions above. Put 1 March 2027 in the calendar with a reminder in early December. If you would rather hand the audit to someone who does this regularly, our Shopify support and maintenance service covers exactly this, for brands across Glasgow, the UK and further afield. Get in touch and we will tell you honestly whether you have a problem worth paying us to fix.